Mössbauer effect studies of Dy(Mn0.4-xAlxFe0.6)2 intermetallics

Both 3d subbands in the Dy(Mn0.4Fe0.6)2 compound are filled up only partially with 3d electrons. So, it was interesting to study the consequence of Mn/Al substitution in the Dy(Mn0.4 xAlxFe0.6)2 series. The cubic, MgCu2-type, Fd3m crystal structure was observed across the series. However, for x = 0.35 and 0.40 a stoichiometric admixture of the hexagonal, MgZn2-type, P63/mmc structure was evidenced. Mössbauer effect measurements at 57Fe nuclei were performed at 77 K. The magnetic hyperfine field decreases vs. the aluminium content x. This dependence is related to the possible 3d-electron band structure.